Welcome to the nursing world! I obtained my ADN last May, so the needs of the program are still very fresh in my mind.
My best piece of advice is to always keep your cool. As Accolay alluded to, many instructors can be 'crabby', to put it mildly. In clinicals, for example, maybe you're taking 5 min at a computer to look up the lab values/new orders/ test results for your patients, because you just finished your rounds and know you have to give a full SBAR report on them before you can go to lunch....the instructor comes by and loudly chides you in the hallway for sitting around when you should be doing patient care. You give them your reasoning, but they don't want to hear it, so you log out of the computer, go find something hands-on to do with the patient...and then you get a second tongue-lashing for being unprepared to give SBAR later!
Keep your cool. Be professional. Sometimes it feels like they WANT to see you fail, or like they are doing everything in their power to break you. I saw so many students crack and run off at the mouth because they could not keep their cool and got overwhelmed... and for whatever reason, they didn't make it though the program. You have your reasons for doing what you do, and so do they. Like not.done.yet said, they feel the pressure of preparing you for an independent nursing role in a limited amount of time, and they also feel the stress of keeping in the clinical site's good graces....they will be HARD on you. I always found it helpful to "debrief" later, off the floor - either during lunch, in their office the next day, or asking them to meet with you quickly after clinicals: don't complain, ask pertinent questions like "My understanding is that you were upset I took too long looking up lab values for this patient. Is there an easier and quicker way to obtain this information you could help me with?" Sometimes I got short, sharp replies, most times I got helpful answers, and rarely, I got an apology for misunderstandings. But I always showed a willingness to communicate professionally and self-improve.
My room mate is going though the "semester from hell" in our local program. I reminded her that at the end of it all, when you pass the class, when you pass the NCLEX....you will then likely need to ask your clinical instructors for one last favor - job references. Sometimes you'll ask them for a letter of recommendation, sometimes to fill out an emailed survey from your prospective employer, maybe just a phone call.....but you will be asking them for a BIG favor: they are your friends, even when it does NOT feel like it
As far as the classes themselves, my advice is roughly the same: keep your cool, come prepared, organize your time to make room for study. Don't get discouraged if you don't make the grade you want: turn to your instructors for help - most might seem like battle axes, but they are happy to help a student who asks!
You seem like a mature person who has a lot of personal experience with professional communication to draw on - you got this!